1966440

Appears in sequences

• Number of minimal covers of an n-set that cover exactly 3 points uniquely.at n=7A003467
• Triangular array read by rows. T(n,k) is the number of minimal covers of an n-set with exactly k points that are in more than one set of the cover, n>=0, 0<=k<=max(0,n-2).at n=45A282575